Method and system for managing communications within a collaborative data processing system

ABSTRACT

The method and system of the present invention permits management of communications within a collaborative computer-based system. The collaborative computer-based system includes multiple display devices, a shared data object that is simultaneously accessible by multiple users within the system. Portions of the shared data object may be displayed on the display devices and cursors are provided within the shared data object. Each of the cursors is associated with one of the users. In managing communications within the collaborative computer-based system, a region within the shared data object may be designated. A designated message is then automatically transmitted in response to selected activities of one or more users within the designated region for the shared data object.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application contains subject matter related to co-pendingapplication Ser. No. 07/816,623, filed Dec. 31, 1991, entitled METHODAND SYSTEM FOR IDENTIFYING USERS IN A COLLABORATIVE COMPUTER-BASEDSYSTEM, Attorney Docket No. RO9-91-061, application Ser. No. 07/816,451,filed on Dec. 31, 1991, entitled CURSOR LOCK REGION, Attorney Docket No.RO9-91-063, and application Ser. No. 07/816,459, filed on Dec. 31, 1991,entitled USER SELECTABLE LOCK REGIONS, Attorney Docket No. RO9-91-062,and assigned to the assignee hereof and incorporated by referenceherein.

BACKGROUND OF THE INVENTION

1. Technical Field:

The field of the invention relates to a collaborative computer basedsystems and more particularly to a modified "What You See Is What I See"multiuser interface for a collaborative editor. Still more particularlythe invention relates to a method of protecting user selectable blocksof a shared data object in a collaborative computer based system fromsimultaneous manipulation originating with other users.

2. Description of the Related Art:

A collaborative system may be defined as a real-time computer basedenvironment coordinating individual efforts toward completion of a task.The task or subject of a group's attention may be a document, aproduction schedule, a computer program, a product design, or any othertask, solution of which is represented by the organized expression ofinformation. Construction of that expression is presumed aided by theefforts of more than one person and particularly by the simultaneousefforts of more than one person.

A computer network is typically the vehicle for coordinating work. Thesubject of the work is typically structured as one or more shared dataobjects stored in memory accessible over the network. The machine forconstructing the data object is software, such as a text editor or database management facilities. The user accesses the shared data objectthrough multiuser interface facilities supported by the network.

A shared data object is one which is simultaneously accessible to aplurality of users over the network. Such data objects can include, forexample, word processing documents, design drawings and spread sheets. Ashared data object is a data object to which more than one user at atime is permitted some type of access.

Thus, a common issue facing designers of collaborative systems is thetype of concurrent access permitted each of a plurality of users. Thiscore issue has a number of subsidiary issues. User access can be limitedto the ability to read an object, but more commonly includes some rightsto manipulate or change the object. For example: Who among the users ispermitted rights to change the data object? Shall each user be shown thesame representation of the data object? How free are users to be inchanging their viewpoint of the shared data object?

A user has access to a shared data object through a multiuser interface.The interface typically includes a video monitor under the control ofthe user's local workstation, through which views of the shared dataobject are displayed. The interface is supported by software allowingmultiple simultaneous access to an object with the right to manipulatethe contents of the object. The general characteristics of one categoryof common multiuser interface are referred to as the "What You See IsWhat I See" (WYSIWIS) concept. In strict form, each user sees exactlythe same thing, from the same viewpoint, with each user being givenapparent immediate rights to manipulate the shared object. All usercursors are simultaneously displayed. Updates are transmitted to eachparticipant, allowing the participants to see what is being done as itis done. In practice the WYSIWIS concept is partially relaxed. Forexample, users are typically permitted to select their point of view.User selected points of view are known as private views of publicobjects. In a word processing document a user may select a portion of adocument of current interest to that user as a private view.

While the WYSIWIS concept has been relaxed for convenience sake, it hasalso been relaxed as a concession to limits in the technology. Considerthe example of collaborative work on the text of a word processingdocument. Each user having current access to the document has a windowgenerated on the video monitor of his or her local workstation, withtext taken from the document reproduced in the window. Each user willhave one text cursor, indicating the point in the document where theuser may make changes. In strict WYSIWIS, all text cursors are to bedisplayed. In practice, the inability to distinguish ownership of acursor on sight has proven confusing, sometimes requiring suppression ofprivate cursors, except the user's own, from a user's video monitor.

Conflicts or collisions in user actions, such as simultaneous attemptsto change the same word in a word processing document, can also causeproblems. In strict WYSIWIS, conflicts are allowed to occur. Each useris given an impression of immediate accessibility. In a setting wherethe workstations are all in one room, or a form of teleconferencing isoccurring, permitting such collisions is tolerable because theparticipants can settle the dispute by conversation. Collisions are lesstolerable where the usual communication between users is that which isimplied by changes in the shared document.

Additionally, users of applications employing multiuser interfaces incollaborative systems encounter problems in coordinating activities withother users. For example, in a collaborative editor, several users maybe making changes to a document. In such an environment, it is veryimportant that the users understand what they are responsible for doingand what their role is in the changing of the document. In addition, itis also important that the users of the document understand what statevarious parts of a document are in. As a result, it would be desirableto have a method and system for coordinating activities between varioususers in group ware applications. Additionally, users of multiuserinterface applications often have difficulty in communicating with otherusers while editing and changing documents.

Therefore, it would be desirable to have a method and system in a dataprocessing system for allowing a user to select regions within a sharedobject for utilization in the automatic transmission of messages withina document.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a methodof enhancing cooperative work in a collaborative computer system.

It is another object of the present invention to provide a collaborativeediting system for utilization within shared data objects.

It is yet another object of the present invention to provide a modified"What You See Is What I See" (WYSIWIS)interface.

It is still another object of the present invention to provide a methodof protecting user selectable blocks of a shared data object incollaborative computer based system from simultaneous manipulationoriginating with other users.

The foregoing objects are achieved as is now described. The method andsystem of the present invention may be utilized to manage ofcommunications within a collaborative computer-based system. Thecollaborative computer-based system includes multiple display devices, ashared data object that is simultaneously accessible by multiple userswithin the system. Portions of the shared data object may be displayedon the display devices and cursors are provided within the shared dataobject. Each of the cursors is associated with one of the users. Inmanaging communications within the collaborative computer-based system,a region within the shared data object may be designated. A designatedmessage is then automatically transmitted in response to selectedactivities of one or more users within the designated region for theshared data object.

The transmission of the selected message may be triggered by variousactivities. For example, the selected message may be transmitted inresponse to a cursor being present in the region at the time the regionis designated. Additionally, the message may be transmitted in responseto a cursor entering the designated region after it has been designated.Other activities, such as altering data within the region or copyingdata within the region, also may be utilized to trigger transmission ofthe selected message.

The selected message also may be transmitted to one or more users. Forexample, the designated message may be transmitted to the user definingthe region, to the user performing the selected action within the regionor to a third party designated by a user.

The above as well as additional objects, features, and advantages of theinvention will become apparent in the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are setforth in the appended claims. The invention itself however, as well as apreferred mode of use, further objects and advantages thereof, will bestbe understood by reference to the following detailed description of anillustrative embodiment when read in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a pictorial view of a local area network with which theinvention is advantageously employed;

FIG. 2 is a pictorial view of a window generated by computer graphicssystem to support the user interface of the invention;

FIG. 3 is a pictorial view of a window opened to a target textual objectfor editing;

FIG. 4-7 are pictorial views of a window opened to a target graphicalobject as the window is edited;

FIG. 8 is a pictorial view of a window generated on a user displaydevice wherein broadcast or notification regions may be defined inaccordance with a preferred embodiment of the present invention;

FIGS. 9A-9C are pictorial views of windows opened to select lock modesand user selectable regions for utilization with the system and methodof the present invention;

FIG. 10 is a pictorial view of a window for a user interface relating tocontrol features of the present invention;

FIG. 11 is a pictorial view of a window for a user interface relating tocontrol features of the present invention;

FIG. 12 depicts a pictorial view of a window opened to control optionsfor selecting notification mode parameters in accordance with apreferred embodiment of the present invention;

FIG. 13 is a pictorial representation of a window opened to controloptions for selecting broadcast mode parameters;

FIG. 14 is a pictorial view of a window including a notification regiondisplayed to a user designated to receive a notification message;

FIG. 15 is a pictorial view of a window including a broadcast regionoverlaid on top of a window in accordance with a preferred embodiment ofthe present invention;

FIGS. 16A-16D are block diagrams of a local area networks illustratingdistribution of data objects supporting the system and method of thepresent invention;

FIGS. 17A and 17B are depictions of data records used in practicingfirst and second embodiments, respectively, of the present invention;

FIG. 18 is a high level flow chart depicting access by a client to acollaborative data processing system;

FIG. 19 is a high level flow chart depicting operation of acollaborative editor at a client terminal incorporating the method andsystem of the present invention;

FIG. 20 is a high level flow chart depicting operation of acollaborative editor at a server incorporating the method and system ofthe present invention;

FIGS. 21A, 21B, and 21C depict a flow chart illustrating operation ofthe collaborative editors of FIGS. 19 and 20 relating to response to acommand received from a user of the system;

FIGS. 22A and 22B are a flow chart relating to update of a clientdisplay in a group editing system provided by the present invention;

FIGS. 23A and 23B are flow charts relating to determination of whether acursor position is locked against editing through that cursor in firstand second embodiments of the invention;

FIGS. 24A and 24B are flow charts relating to first and secondembodiments of the invention, respectively, providing for updating ofcursor associated lock regions within a shared data object;

FIGS. 25A and 25B are flow charts relating to first and secondembodiments of the invention, respectively, providing for user selectionof regions within a shared data object;

FIG. 26 is a flow chart relating user establishment of a lock regionfrom a select region;

FIG. 27 is a flow chart relating to user designation of a select regionas an associated region;

FIG. 28 is a flow chart relating to removal of a look or associationdesignation from a region; and

FIGS. 29A and 29B are flow charts relating to first and secondembodiments of the invention providing for detection of lock conflictdeterminations made upon attempts to select a region; and

FIG. 30 depicts a flowchart for processing local notification andbroadcast region in accordance with a preferred embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the figures and in particular with reference toFIG. 1, a pictorial representation of a local area network which may beutilized in accordance with the method of the present invention isdepicted. Local area network 8 supports a collaborative computer basedediting system relating to a data object stored on a server. Local areanetwork 8 provides data communication over a transmission channel 10between a plurality of personal computers 12. Computers 12 within thedepicted system are preferably provided by utilizing an IBM personalcomputer, an IBM Personal System/2 available from International BusinessMachines Corporation or other similar system. "Personal System/2" is aregistered trademark of International Business Machines Corporation. Asthose skilled in this art will appreciate, computers 12 generallyinclude a keyboard for receiving user inputs in a video display deviceto send messages to the user of the local area network. One of computers12 operates as a server for the network 8. The server may, for example,be a larger computer such as the IBM Application System/400. ApplicationSystem/400 computers are available from International Business MachinesCorporation. "Application System/400" is a registered trademark ofInternational Business Machines.

FIG. 2 depicts a pictorial representation of a window including examplesof features of a multiuser interface supported by the present invention.Window 18 is a conventional window as would appear on a display screenon a computer 12. A locally generated mouse pointer 22 is available foroperating control features of the window by a user utilizing a mouse.The term "mouse" may refer to any type of operating system supportedpointing device including, but not limited to a mouse, track ball, lightpen, touch screen and the like.

Window 18 includes a title bar 24 identifying the shared data objectaccessed by the user. Display field 27 exhibits a private view 28 of ashared data object. Cursors 20 and 26 also appear in display field 27.Cursor 20 is a cursor assigned the user of private view 27. Cursor 26 isa cursor assigned another user who has access to the same shared dataobject and who, at least in part, is accessing a portion of the shareddata object extending into private view 28. Cursor 20 respondspositionally to movement commands generated by the user. Cursor 26 willmove about the screen and possibly out of the display field 27 dependingon commands from a remote site. Shared data object may be a wordprocessing document represented in portion by lines of text reproducedin display field 27, but could also be a graphical image or other typeof document.

Cursors 20 and 26 have display attributes resulting in visually distinctappearances, indicated by the solid shading of cursor 20 and thecross-hatching of cursor 26. In the preferred embodiment, the cursorsappear in distinguishing colors.

FIG. 3 is a pictorial view of a window 102 generated on a user displaydevice. A text editor function is associated with window 102. Within adisplay field 104 is a private view of a target textual object. A usermay edit the target textual object by positioning his or her assignedcursor 108 at the point at which the user wishes to make a change or toadd material. Cursor 108 appears embedded in a floating, transitory lockregion 106, which extends to the word or word equivalent object in whichthe cursor is currently located. Cursor 108 and lock region 106 appearas colored areas on a color monitor, with the particular colors of thecursor and lock region and the background appearance of the lock regionindicating the owner of the cursor and the lock region, as well as thetype of lock region.

A region 110 is marked by coloring unique to a particular user toindicate some association with that user. Region 110 may identifyownership, or it may be locked against editing by other users. Thesecond user cursor 114 appears in the view of display field 104,embedded in a floating lock region 112. Again cursor 114 and lock region112 are of unique colors, identifying the owner of the cursor. Region110 may be associated with the owner of cursor 108, 114, or some thirdcurrent or past client of the collaborative editor.

FIG. 4 is a pictorial view of a window 116 opened to a shared graphicalobject for editing using a collaborative graphic editor. Three users,represented through cursors 130, 138 and 140, appear in the view of theshared graphical object appearing in display field 117. A plurality ofsubobjects appear in the view including a text segment 118, a linedrawing 120 of a train, a second text segment 122, a line drawing 123around spacecraft object 124, moon object 125, space traveler object 126and planet object 127, as well as a third text segment 128. A visualattribute of each region, or its border, indicates some associationalstatus between the region and a user. Regions 142, 134 and 123 are userselected regions and may be cancelled by their respective establishingusers at any time. The user selected regions may be locked againstmanipulation by other users, or may be used to merely indicateownership.

Each user cursor 130, 138 and 140 has its own distinguishing color. Eachcursor appears within one of cursor lock regions 132, 136 and 144, whichalso have distinguishing visual attributes, preferably a unique color.Again, the cursor lock regions are floating and transitory, arising whena cursor is free of the user selected region or cursor lock region ofanother. The shape and size of cursor lock regions are selectable by theuser. For example, the owner of cursor 138 has selected a circularcursor lock region 136, while the owner of cursor 140 has selected asquare cursor lock region 144. The owner of cursor 130 has selected anobject lock region 132, which takes on the shape of underlying object125.

FIG. 5 is a pictorial view illustrating entry of a fourth user,represented by cursor 146, to the view of display field 117. The user ofcursor 146 has initiated selection of a new region by generating aselect point 145, indicated by an "X" displayed in display field 117.Cursor 146, like other cursors, is identified as to its user by a color.It is surrounded by a square cursor lock region 148, which is alsoidentified by color as to owner.

FIG. 6 is a pictorial view illustrating completion of a select region bythe user of cursor 146. By selection of a second select point 147 and byrequest of construction of a rectangle, a select region 150 is paintedto display field 117. Select region 150 is indicated by close hatchingin the figure, and like other user associated regions, has some visuallydistinguishing attribute to identify it to other users as to owner andtype. A display style is preferred for making this indication.

FIG. 7 is a pictorial view illustrating selection by the user of cursor146 of an associational type for select region 150. Again, such a typemay be simple "ownership" or creation of a user select lock region. Theassociational change is indicated by a change in the visual attribute,or display style, of the region, here for a user select lock region 151.Different types of associations may also be given different visualattributes such as different forms of cross-relating or color shading.

FIG. 8 is a pictorial view of a window 600 generated on a user displaydevice wherein broadcast or notification regions may be defined inaccordance with a preferred embodiment of the present invention.Depicted within display field 602 is region 604, which may define eithera broadcast or notification region. Three users, represented throughcursors 606, 607, and 608, appear within display field 602. Cursor 606and cursor 608 appear within region 604. Users with cursors withinregion 604 may receive a broadcast or notification.

FIGS. 9A-9C are pictorial views of two windows 152 and select modewindow 154 opened to control features for selecting cursor lock modeparameters. Referring to FIG. 9A, through display field 153 and mousepointer 22 a user may select to have a lock region automatically attachto his or her assigned cursor in a text application by selection of theON or OFF buttons. Upon selection of automatic association, the userselects a mode of lock. Character, word and line modes are generallyappropriate for text editing. Although one being skilled in the art willappreciate that other modes such as sentence, paragraph or page may beutilized. FIG. 9B depicts the selection of a lock region for an image orgraphics application. For example, selection of the "POLYGON" button isa mode typically more appropriate for pictorial or graphical editing.The "user defined" mode points a user to define an irregular lock regionby specifying various vertices. Alternatively, an object containinggraphical or textual information may be selected as a lock region byselecting the "OBJECT" button. Similarly, a user may select the "SQUARE"or "CIRCLE" buttons to elect a lock region in those shapes.

FIG. 9C shows how a user may define various shapes for a select region.Display field 155 .of window 154 includes three buttons selectable bymouse, a "SQUARE" button, a "CIRCLE" button and a "POLYGON" button.Selection of any of the three requires identification of certainparameters, such as radius for a circle. A plurality of boundary pointswill need to be specified for the POLYGON selection. After specifying aselect mode in this manner, subsequent select operations by that userwill take on the shape specified by the chosen select mode.

A network server generates default colors for the cursor assigned eachuser upon log on to the system. However, the system affords a user theright to locally modify the interface in a number of ways. Suchmodifications are supported through window 34 of FIG. 10 and window 40of FIG. 11. As illustrated in FIG. 10, a window 34 is labelled in itsname bar 36 for "Local Display Options." Four selections are providedrelating to color mode 38. The selections are: full, where each userreceives a distinct color; "two color", which provides one color for theuser's own cursor and another color for all other user cursors; a "greyscale", which varies the intensity of each cursor on a monochromescreen; and a "fill pattern", which uses backgrounds such as hatching,parallel lines or flashing to distinguish one cursor from another. Thecolor mode selected extends to user selected and defined association oflock regions as they occur within the shared data object and to thecursor assigned a user.

A palette option 39 relates to a selection of colors in the full colormode. The default button invokes the system established colors. A custompalette button generates window 40 illustrated in FIG. 11. In window 40,a user can select new colors for each user. Color selection allows thosewho are partially color blind to select a palette of distinguishingcolors. A user/color table 44 appears in the display field of window 40.Upon selection of a particular user, a particular color may be selectedfrom color wheel 46. The intensity of the color may be varied bymanipulating a scroll bar 50. Selection is made by button from amendbuttons 48. Buttons 48 also include a cancel button and a defaultselection button, which restores the originally assigned color to aparticular user.

FIG. 12 is a pictorial view of a window 610 opened to control optionsfor selecting notification mode parameters in accordance with apreferred embodiment of the present invention. Window 610 overlayswindow 611, in which the user may define region 613 as a notificationregion in accordance with a preferred embodiment of the presentinvention. Notification message 612 allows a user to enter text to besent to selected users in response to the presence of the selecteduser's cursors within the notification region. "Triggered by" option 614allows the user to the select which users will trigger the sending of anotification message. The notification message may be sent to varioususers, as selected utilizing "To" option 616. The notification messagemay be sent to the user defining the notification region, to all users,to the users triggering the notification message, or to selected users.

FIG. 13 is a pictorial representation of a window 620 opened to controloptions for selecting broadcast mode parameters, in accordance with apreferred embodiment of the present invention. Window 620 may overlaywindow 621, in which the user has defined region 623 as a broadcastregion, in accordance with a preferred embodiment of the presentinvention. A user defining a broadcast region may select users who areto receive the broadcast message, utilizing to option 624. The userdesignate "All" or "Selected" users to receive a broadcast message inaccordance with a preferred embodiment of the present invention. Themessage is defined utilizing broadcast message option 622, which allowsa user to enter a message for broadcast to other users. Window 620 alsoincludes buttons 626 and 628. Button 626 is utilized to elect thoseoptions within window 620 and button 628 is utilized to cancel anyoption selected within window 620.

FIG. 14 is a pictorial view of a window 640 which includes anotification window 632, which is displayed to a user designated toreceive a notification message. Notification region 632 displays thenotification message: "This section has been updated to reflect theplan". Notification window 632 also includes the author of thenotification message and the user triggering the notification message(User Y), in accordance with a preferred embodiment of the presentinvention. Notification window 632 also includes button 634, which maybe utilized to cancel the message, after the user has read the message.

FIG. 15 is a pictorial view of a window 640 which includes a broadcastwindow 642, overlaid on top of a window 640 in accordance with apreferred embodiment of the present invention. Broadcast region 642includes a broadcast message and identifies the author of the message.Broadcast window 642 also includes buttons 644 and 646. Button 644 maybe selected by the user after the user is finished reviewing thebroadcast message within broadcast window 642. Button 646 may beselected by a user to reply in response to the message in broadcastregion 642, in accordance with a preferred embodiment of the presentinvention.

FIG. 16A depicts a block diagram of local area network 8 for supportinga collaborative computer based editing system 6 in the preferredembodiment. Server 12 communicates with computers 12a-12n over acommunications channel 10. Local area network 8 is depicted in a tokenring geometry, however, other geometries are possible. Server 12 is aconventional computer such as an IBM Personal System/2 or AS/400 systemprogrammed to practice this invention, and includes a central processingunit 60, a memory 64, and a network adapter 62 for formatting outgoingtransmissions and for deformatting incoming transmissions. Server 12includes a hard drive unit 56 storing a plurality of shared data objectspending a request for access by one or more users. Such a requestresults in the transfer of the data object to computer memory 64 overdata bus 58. A number of objects exist within memory 64. An operatingsystem and local area network server 66 are represented as one object.An editor program 68, an association/lock list 70 and a cursor list 72are associated with a particular edit object, here a first edit object74, to provide a cooperative machine for generation and modification ofthe shared data object. Additional edit objects may simultaneouslyexist.

Users access the shared data objects through computers 12a-12n. Computer12b is a typical example. A computer 12b operates as a personalworkstation communicating with computer 12. Schematically the personalworkstation 12b is substantially similar to computer 12, and includes anetwork adapter 78, a display adapter 84, a hard drive unit 90, acentral processing unit (CPU) 82 and an addressable memory 88.Components of personal workstation 12b transfer data over a data bus 83.CPU 82 directly controls input peripherals 80 which may include akeyboard and a mouse. Display adapter 84 drives a display device 86,upon which windows are generated. Memory 88 includes a replica 92 ofdocument 71 accessed by the user of personal workstation 12b. Replica 92is accessed to change a user's personal view of the shared data objectwithout the necessity of burdening network 10 for transfer of the datato support the private view. Also present is a command structure 94 foruse in establishing a communications session on network 8.

The machine for effecting changes in first edit object 74 are itsassociated editor 68, association/lock list 70 and cursor list 72.Document 71 constitutes association/lock list 70, cursor list 72 and atarget edit object 74. Cursor list 72 is a record of each user currentlyaccessing the first edit object 74. Association/lock list 70 includeslock regions generated by a movement of a cursor into an unlocked areaof edit object 74 and those lock regions as have been established byusers as well as other regions associated with users. Cursor list 72 isupdated whenever a new user accesses edit object 74 or when a user logsoff an edit object. Entry records in association/lock list 70 may varywith movement of cursors and with the exercise of select and deselectoperations by users. An association/lock record includes a start point,an end point, an association type and a user identification.

FIG. 16B depicts a block diagram of an alternate embodiment ofsupporting collaborative computer-based system 6. FIG. 16B is similar toFIG. 16A, except that replicas 92 of document 71 for clients 17A-17B arecontained in memory 64 and executed within server 12. Input/outputprocessor 61 communicates with a plurality of non-programmableworkstations (NWS) 85. In this embodiment, server 12 becomes a singlecomputer system running multiple processes, such as an IBM ApplicationSystem/400 attached to multiple non-programmable workstations. Eachnon-programmable workstation 85 has a corresponding replica 92 in memory64.

FIG. 160 depicts a block diagram of local area network 8 for supportinga collaborative computer based editing system 6 in the preferredembodiment. FIG. 16C is similar to FIG. 16A, except that document 71further includes notification/broadcast record/list 73.Notification/broadcast record/list 73 includes regions defined fornotification or broadcast messages as have been established by users.FIG. 16D depicts a block diagram of an alternate embodiment ofsupporting collaborative computer-based system 6.

FIG. 16D is similar to FIG. 16B, except that document 71 furtherincludes notification/broadcast record/list 73. Notification/broadcastrecord/list 73 includes broadcast and notification regions asestablished by other users in accordance with a preferred embodiment ofthe present invention.

FIGS. 17A and 17B illustrate data records 160, 162, 163, 164, 166, and167 used in practicing first and second embodiments, respectively, ofthe invention. The embodiments relate to collaborative text editing andcollaborative graphical or pictorial editing.

The current user list for a collaborative text editor includes a list ofpointers to cursor records 160, one of which is illustrated in detail.One cursor record exists for each current user. A record 160 includes aunique identifier for the cursor. A current position record indicatingthe line of text and the offset within the line for the cursor ismaintained, subject to update with each command resulting in a change ofposition. Record 160 includes two related fields utilized in selectionof a new region for locking or other purposes. A select on field is aflag indicating a select region is active. A select region is a freshlyidentified region not identified as to associational type. The selectlock field is a pointer to a record for the select region.

The user lock list is a list of pointers to lock records of regionswhich are locked against other users. The cursor lock is fieldcontaining a pointer to a lock record for the floating lock associatedwith the cursor. A pointer may or may not be present. Finally, anAssociation region list is a collection of fields containing pointers to"Association/Lock" records which are associated in some way with a user,other than by being locked against manipulation by other users.

Record 162 is characteristic of such Association/Lock records. Therecord includes the identification number of the owning cursor. Theassociation type is identified, e.g. select lock, user lock, cursorlock, ownership, et cetera. Fields are provided to identify thebeginning and end of the region, in terms of line and offset.

Record 163 is characteristic of a "notification" record. The recordincludes the identification number of the owning cursor. The "To User"field includes a list of users to which a notification message may besent and the "Author" field defines the user creating the notificationmessage. The "From User" field defines who can trigger the display of anotification message. The "Message" field defines the message to be sentto users listed in the "To User" field. Fields are also provided toidentify the beginning and end of the region, in terms of line andoffset values.

FIG. 17B illustrates data structure records utilized for a collaborativegraphics editor. The current user list for a collaborative graphicseditor includes a list of pointers to cursor records 164, one of whichis illustrated in detail. One cursor record exists for each currentuser. A record 164 includes a unique identifier for the cursor. Acurrent position record indicating the X-axis and Y-axis coordinates inthe graph or picture for the cursor is maintained, subject to updatewith each command resulting in a change of position. Record 164 includestwo related fields utilized in selection of a new region for locking orother purposes. A select on field is a flag indicating a select regionis active. A select region is a freshly identified region not identifiedas to associational type. The select lock field is a pointer to a recordfor the select region.

The user lock list is a list of pointers to lock records of regions,which are locked against other users. The cursor lock is fieldcontaining a pointer to a lock record for the floating lock associatedwith the cursor. A pointer may or may not be present. Finally, anAssociation region list is a collection of fields containing pointers to"association/lock" records, which are associated in some way with auser, other than by being locked against manipulation by other users.

Record 166 is characteristic of Association/Lock records for acollaborative graphics editor. The record includes the identificationnumber of the owning cursor. The association type is identified, e.g.select lock, user lock, cursor lock, ownership, et cetera. A fieldidentifies the shape of the region, including squares, circles and userdefined polygons. An ordered list of defining points, i.e. vertices, aremaintained for the region. The list ordering is provided to identify thesequence of points connected by the boundary line of the polygon.

Record 167 is characteristic of a notification record for acollaborative graphics editor. The record includes the identificationnumber of the owning cursor. A "To User" field is provided for definingusers who may receive a notification message. The "Author" field definesthe user creating the notification message. The "From User" fielddefines who can trigger the display of a notification message. The"Message" field is utilized to define the notification message fortransmission to users listed in the "To User" field. A field identifiesthe shape of the region, including squares, circles, and user definedpolygons. An ordered list of defining points, il.e., vertices, aremaintained for the region. The list ordering is provided to identify thesequence of points connected by the boundary line of the polygon.

FIG. 18 is a high level flow chart illustrating access by a client to acollaborative editing system of either the text or graphics/pictorialtype. The initial state of the system is to have a server waiting forclient requests for connection (block 200). The server is normallyblocked and requires little in the way of computation resources of thehost machine. Upon a user request, a connection is established. Decisionblock 202 reflects that the user may be a pseudo user, utilized to passa terminate command to the server by setting a terminate flag. The YESbranch from block 202 reflects such a flag. More typically however, anactual user is connected, resulting in execution of block 204, which isestablishment of an Asynchronous Client Manager for the requestingclient. The client manager is illustrated in FIG. 20 below.

Referring now to FIG. 19, a high level flow chart depicting operation ofa collaborative editor for either text or graphics application at aclient is depicted. The process begins at block 206 with identificationof a shared document to edit. Next, at block 208, the client contactsthe server and requests the document identified at block 206. Thetransmission out of the request is indicated by the letter "A". Receiptof the transmission by the server, also indicated by the letter "A", wasindicated at block 200 of FIG. 18 above. At block 210 the clientreceives its copy of the document from the server, indicated by theletter "B". The document includes a target object for editing, thecursor list, cursor records, and association/lock records. The documentis stored in the client memory. Finally, at block 212 a local editor isinitialized. Editing can now begin.

Next, decision block 214 is utilized to determine if an input has beenreceived from a user. If so, decision block 216 is utilized to determineif the command was valid or not. If the command is not valid, theprocess warns the user from block 218 and returns to block 214 analyzethe next user entry. If the command is valid, block 220 is utilized totransmit the edit command to the server. The transfer point between thelocal editor program and the server editor program is indicated by theletter "C".

Next, response of the local editor to valid commands is detailed. First,block 215 illustrates a determination of whether or not a new cursor hasbeen received from the server, indicated by transfer point "F." If so,the cursor is added to the local document, as depicted at block 217. Ifno new cursor is received from the server, the process passes to block222 where a determination is made as to whether or not an edit commandhas been received from the server. Edit commands can originate eitherlocally or from another user. However, no edit command is acted uponuntil received by the client from the server. Accordingly, blocks 214and 222 are repeatedly executed for the purpose of identifying commandsfor transmission to server and for receiving commands from the server.

Upon return of an edit command from a server editor, indicated by antransfer point "D", block 224 is utilized to perform the command on thelocal document. It will become clear from the discussion below that suchcommands can come from client managers for other users. The operationsoccurring in block 224 are explained in detail below with reference toFIGS. 21-29. They include edit operations, region associationoperations, cursor movement and other steps. Decision block 226 isutilized to determine if the command is a quit command or an exitcommand. If so, the process passes to block 227 which illustrates thedeletion of the owner's cursor and block 229 depicts a determination ofwhether or not the cursor deleted was this client's cursor. If not, theprocess returns to block 214 to await the next command. If the cursordeleted was this client's cursor, block 228 is utilized to close thelocal document and to perform any other local cleanup functions, afterwhich the local process is discontinued. The NO branch from block 226returns to block 214 and the process awaits the next command.

FIG. 20 is a high level flow chart depicting a client manager andcollaborative editor being processed at the server. The process beginsat block 230, which is utilized to determine if the request targetobject or document is currently being edited by anyone else. If not,block 232 is utilized to open the document and to initialize theappropriate data structures to support collaborative editing. Once anopen document is obtained, or if it already existed, block 234 isutilized to create a cursor record for the new user. A copy of thedocument, including the updated cursor records and lock records, if suchexist, is downloaded to the client terminal, indicated by the transferpoint "B". The new cursor is distributed to all other clients, asindicated by fan-out point "F." Block 236 reflects addition of the newuser to the list of clients accessing the document.

Management of client access to the target object within the documentbegins at block 238. Upon receipt of an edit command from the client,indicated at exchange point "C", the process utilizes block 240 toobtain a semaphore to the server version of the document. Upon obtainingthe semaphore, the client manager has exclusive access to the documentfiles. Access by clients to the document is thus serialized to preserveconsistency. Block 242 may now be utilized to perform an edit operationon the server version of the document. These operations are explained indetail below with reference to FIGS. 21-29. Next, block 246 is utilizedto distribute the edit command to the all of the clients attached to thecurrent document for parallel operation on local versions of thedocument, as indicated at fan-out point "D." As will now be clear, theclient editor depicted in FIG. 19 may receive edit commands from aplurality of client managers. Next, block 248 reflects determination ofwhether last edit command was a quit originating with this clientmanager's client. If not, the process passes to block 250 whichillustrates the release of the semaphore to the document.

A client instruction to quit results in utilization of block 252 toremove the client from the list of clients attached to the document andin deletion of the client's cursor record. Block 254 is utilized todetermine if a client was the only remaining client attached to adocument. If yes, block 256 is used to close the document and to performany required cleanup steps. Next, block 257 illustrates the release ofthe semaphore for the document. The client manager for the withdrawingclient only is closed.

FIGS. 21A and 21B illustrate those operations which occur at blocks 224and 242 of a client editor running on a local terminal and a clientmanager running on a server, respectively. The operations are largelyparallel, however, such differences as exist are noted. Referring now toFIGS. 21A and 21B, a flow chart depicting operation of the collaborativeeditor is illustrated. The process is initiated at block 258 in FIG. 21Aupon receipt of a command and a cursor with which to execute thecommand. Block 260 is utilized to determine if the command is one whichwill modify the target object of the document in some way.

If the received command is one which modifies the target object, block262 is utilized to determine if the cursor is located at a position inthe target object which is locked against that cursor. If not, block 264is utilized to perform the application command which modifies the targetobject. This may involve commands similar to commands utilized by agraphics editor, such as Corel Draw, available from Corelsystems Corp.,1600 Carling Avenue, Ottawa, Ontario, or any one of a number of texteditors and may include save and edit commands. Appropriate modificationof the display is also made, if the operation occurs in the clienteditor's view. Where the target object is locked, the change is notentered and the process is returned to the client editor or clientmanager, as appropriate. Determination of target object lock status isexplained below with reference to FIGS. 23A and 23B.

Commands which do not modify the target object of a document includethose commands controlling cursor movement and commands involvingselection and deselection of regions of the target object for locks orother association status. Also among such commands are "saves" of thetarget object and "quit" commands. However, the first group of commandsare of primary concern here. Following the NO branch from decision block260, decision block 266 is utilized to determine if the command was acommand to move a cursor. If so, block 268 is utilized to perform thecursor movement, i.e. to update the cursor record 160 or 164 (see FIGS.17A and 17B) for the cursor. Next, if the process is operating on aclient editor, the display is updated to reflect the new cursor positionas described below with respect to FIGS. 22A and 22B. Next, at step 272the cursor lock is updated (for detail see FIGS. 24A and 24B). As willbe explained in greater detail below, a cursor lock may or may not bereturned, depending upon the new location of the cursor. The process isthen returned to the client editor or manager, as appropriate.

If the received command was not a cursor movement command, the NO branchfrom decision block 266 advances the process to decision block 274.Block 274 is utilized to determine if the received command is a selectcommand, which is utilized to identify a portion of a shared data objectfor some form of association with a user. If so, block 276 is utilizedto perform the selection operation (See FIGS. 25A and 25B below).

If the received command was not a select command, the NO branch fromdecision block 274 advances the process to decision block 278. Block 278is utilized to determine if the received command is a lock command,which is utilized to convert a select region to a user select lockregion in a shared data object. If so, block 280 is utilized to performthe lock operation (See FIG. 26 below).

If the received command was not a lock command, the NO branch fromdecision block 278 advances the process to decision block 282. Block 282is utilized to determine if the received command is an unlock command,which is utilized to remove a user select lock region in a shared dataobject. If so, block 284 is utilized to perform the unlock operation(See FIG. 28 below).

If the received command was not an unlock command, the NO branch fromdecision block 282 advances the process to decision block 286. Block 286is utilized to determine if the received command is an associatecommand, which is utilized to convert a select region to a userassociation region in a shared data object. If so, block 290 is utilizedto perform functions similar to those described above with respect toblock 264, including save and edit commands. (See FIG. 27 below). If thereceived command is not an associate command, the process then proceedsto block 285 for a determination of whether or not the received commandis a broadcast command. If the received command is a broadcast command,the process then proceeds to block 770 via connector Y as depicted inFIG. 21C. Block 770 illustrates a determination of whether or not thebroadcast event is addressed to a local user. If the broadcast event isaddressed to a local user, the process then proceeds to block 772. Block772 depicts the display of the broadcast message to the local user.

Referring back to block 285, if the received command is not a broadcastcommand, the process then proceeds to block 287 for a determination ofwhether or not the received command is a notification command. If thereceived command is a notification command, the process then proceeds toblock 746 via connector Z.

Block 746 is utilized to determine whether or not the event is a remotecancel notification region event. If the event is a remote cancelnotification region event, the process then passes to block 747. Block747 illustrates the locating of the specified region in the notificationregion list and deleting that region. Thereafter, the process proceedsto block 289 in FIG. 21A via connector X. Block 289 depicts a return tothe client editor.

Referring again to block 748, if the event is not a remote cancelnotification region event, the process then proceeds to block 748, whichillustrates a determination of whether or not the event is a remotecreate notification region event. If the answer is YES, the process thenproceeds to block 750. Block 750 depicts the creation of a newnotification region and the addition of that region to the notificationregion list. Thereafter, the process passes to block 289 in FIG. 21A,via connector X.

Block 752 illustrates a determination of whether or not any cursormovement event (including cursors of other nodes) has occurred. Upon theoccurrence of a cursor movement event, the process passes to block 754,which depicts a determination of whether or not more regions are in thenotification region list. If more regions exist in the notificationregion list, the process proceeds to block 756. Block 756 depicts theretrieval of the next region from the list. The process then proceeds toblock 758, which illustrates a determination of whether or not the movedcursor is within this region. If the moved cursor is not within thisregion, the process returns to block 754. If, however, the moved cursoris within the region, the process then proceeds to block 760. Block 760depicts a determination of whether or not the notification region isaddressed to this node's user. If the answer is NO, the process returnsto block 754. The addressing of the notification region to this node'suser results in the process proceeding to block 762. Block 762illustrates a determination of whether or not the system is in a"receive once" mode. If the system is not in a "receive once" mode theprocess proceeds to block 764, which depicts the display of a notice tothe local user.

Next, the process proceeds to block 766. Block 766 illustrates therecording of the notice as being seen by the local user. Thereafter, theprocess proceeds to block 289 in FIG. 21A, via connector X. Referringagain to block 762, if the system is in a "receive once" mode, theprocess proceeds to block 768, which illustrates a determination ofwhether or not the local user has received this notice before. If thelocal user has received this notice before, the process proceeds toreturn 289 in FIG. 21A, via connector X. If the local user has notreceived this notice before, the process then proceeds to block 764. Ifthe command is not a notification command, the process proceeds to block288.

Execution of the remaining possible commands, is illustrated at block288. All operations of the process end in block 289, which illustrates areturn to the client editor or the client manager, as appropriate.

FIGS. 22A and 22B relate to the process of updating a display on a localterminal. Generally no display is provided at a server. A display updateoccurs after modifications to the document have occurred, after a cursormove command, and after an operation relating to user associationregions. The flow chart of FIGS. 22A and 22B relates to the latter twocases and may be presumed to be executed after the operationsillustrated at blocks 276, 280, 284, or 290.

The process of updating a display begins at decision block 292, whichinitiates once again the process of identifying the nature of the editcommand received. Decision block 292 is utilized to determine if thereceived command was a move cursor command. If so, a series of blocks294, 296, 298, 300 and 302 are utilized to illustrate process stepswhich identify the owner of the cursor, determine the color for theowner, determine the new position of the cursor, remove the old cursorand display the cursor at its new position in the designated color.

The process of updating a display continues at decision block 304.Decision block 304 is utilized to determine if the received command isto select a region. If so, a series of blocks 306, 308, 310, 312 and 314are utilized to illustrate process steps which modify the region toidentify it as selected and to identify the selecting user. The stepsillustrated within these blocks specifically provide for identifying theowner of the select region, recovery of a color for the owner, recoveryof a "SELECT" display style, determination of the region in the displayfor which modification of the appearance is required and, finally,painting the region using the owner's color and the SELECT displaystyle.

The process of updating a display continues at decision block 326.Decision block 326 is utilized to determine if the received command is acommand to lock a region. If so, a series of blocks 328, 330, 332, 334,336 and 338 are utilized to illustrate process steps which modify theregion to identify it as looked and to identify the owner. The stepsillustrated within these blocks specifically provide for identifying theowner of the lock region, recovery of a color for the owner, recovery ofa "LOCK" display style, determination of the region in the display forwhich modification of the appearance is required and, finally, paintingthe region using the owner's color and the LOCK display style.

The process of updating a display continues at decision block 340.Decision block 340 is utilized to determine if the received command is acommand to unselect or to unlock a region. If so, a series of blocks342, 344, 346 and 348 are utilized to illustrate process steps whichrestore the region to a "normal" appearance. The steps illustratedwithin these blocks specifically provide for recovery of the normaldisplay color, recovery of a normal display style, determination of theregion in the display for which modification of the appearance isrequired and, finally, painting the region using the normal color anddisplay style.

Referring now to FIG. 22B, the process of updating a display continuesat decision block 350. Decision block 350 is utilized to determine ifany other associations are "ON" within a view. If so, a series of blocks352, 354, 356 and 358 are utilized to illustrate process steps whichmodify the region to identify the association and to identify its owner.The steps illustrated within these blocks specifically provide forrecovery of a color for the owner, recovery of an appropriate displaystyle, determination of the region in the display for which modificationof the appearance is required and, finally, painting the region usingthe owner's color and the appropriate association display style.

The process of updating a display continues at decision block 360.Decision block 360 is utilized to determine if associations are off forregions in a view. If so, a series of blocks 362, 364, 366 and 368 areutilized to illustrate process steps which display the regions in a"normal" appearance. The steps illustrated within these blocksspecifically provide for recovery of the normal display color, recoveryof a normal display style, determination of the region in the display,and painting the region using the normal color and display style. Aftercompletion of a display update processing is returned to the appropriatelocation in the local editor.

FIGS. 23A and 23B are flow charts which illustrate a process relating tothe determination of whether a cursor is locked against editing at itscurrent position. The figures relate to first and second embodiments ofthe invention, that is, a text editor context and a graphics orpictorial editor context, respectively. Referring to FIG. 23A, whichrelates to a text editor, the process begins with the utilization ofdecision block 370 to illustrate a determination if any association/lockrecords, including cursor lock records, exist which have not beenexamined. If not, no lock blocks the operation requesting thedetermination and the process is returned. If such records existhowever, they must be examined. Next, as illustrated at block 372, thenext record is recovered. Decision block 374 is utilized to illustrate adetermination if the record is a lock type, including user locks, selectlocks or cursor locks. If not, the record is irrelevant and the processreturns to block 370. If the record is a lock type, decision block 375is utilized to determine if the user is the owner. If so, the record isirrelevant and the process returns to block 370. Finally, decision block376 is utilized to illustrate the comparing of the position of thecursor and the start and end points of the lock record. If the cursorlies between the start and end points, a lock blocks the use of thecursor to modify the document or to establish a select point. A lockedindication is returned to the host process. If the cursor lies strictlyoutside of the start and end points of the record, the lock is noteffective at the cursor position. The process returns to block 370 forevaluation of the next record. Only upon clearing all records is a notlocked indication returned.

Referring to FIG. 23B, which relates to a graphics editor, the processbegins with utilization of decision block 378 to illustrate adetermination if association/lock records, including cursor lockrecords, exist which have not been examined. If not, no lock blocks theoperation requesting the determination and the process is returned. Ifrecords exist however, they must be examined. Next, as illustrated atblock 380, the next record is recovered. Decision block 382 is utilizedto illustrate a determination if the record is a lock type, includingeither user locks, select locks or cursor locks. If not, the record isirrelevant and the process returns to block 378. If the record is a locktype, decision block 383 is utilized to illustrate a determination ifthe user is the owner. If so, the record is irrelevant and the processreturns to block 378. Finally, decision block 384 is utilized toillustrate a comparison of the position of the cursor with the bounds ofthe polygon formed by the boundary points of the lock record. If thecursor lies within the polygon, a lock blocks use of the cursor tomodify the document or to establish a select point. A locked indicationis returned. If the cursor lies strictly outside of the polygon, thelock is not effective at the cursor position. The process returns toblock 378 for evaluation of the next record. Only upon clearing allrecords is a not locked indication returned.

FIGS. 24A and 24B are flow charts relating updating of cursor lockregions within a shared data object upon movement of a cursor. Referringto FIG. 24A, an update process for a lock in a textual target objectbegins with utilization of decision block 386 to determine if thecurrent cursor lock record is null. If so, operation blocks 388 and 390are used to generate a new cursor lock record and to set a pointer inthe cursor record to the new cursor lock record. Once a cursor lockrecord is available, decision block 392 is utilized to determine if thelock mode for the cursor lock is a character position. If it is, block394 is utilized to change the start and end fields in the cursor lockrecord to equal the current position of the cursor. If the lock mode isnot a character, the process takes the NO branch from block 392 todecision block 396, which is utilized to determine if the lock mode isequal to a word. If it is, the process takes the YES branch from block396 to block 398. Block 398 is utilized to retrieve the current linefrom the target object. Next, block 400 is utilized to determine theoffsets of the start and end of the current word. Next, block 402 isutilized to set the start and end fields in the cursor lock record equalto the start and end of the current word. If, at block 396 it wasdetermined that the lock mode did not equal a word, it is assumed thatthe lock mode equals a line. Along the NO branch from block 396, theprocess utilizes block 404 retrieve the current line from the targetobject. Next, at block 406, the cursor lock record fields for the startand end are set equal to the start and end of the current line.

After setting the start and end fields for the lock record in any mode,decision block 408 is utilized to determine if the new cursor lockrecord conflicts with any other locks (for details of the analysis seeFIG. 29A). If it does conflict, the new cursor lock record is removedfrom the document data structure (block 410) and the cursor record tothe pointer is set to null (block 412). Block 413 then illustrates theupdating of the display. The process then returns to the appropriatepoint in the editing process. If there is no conflict detected at block408, the process returns directly to the appropriate point in theeditor.

An update of a cursor lock in a graphics editing environment is somewhatmore complex. Referring to FIG. 24B, operation block 414 is initiallyutilized to create a new, provisional cursor lock record. The pointerfield in the cursor record is not changed at this time. Next, decisionblock 416 is utilized to determine if the lock mode is equal to asquare. If it is, block 424 is utilized to generate the four absolutecoordinates of the square centered on the current cursor position in theplane of the view. If the shape of the cursor lock region is not asquare, decision block 418 is utilized to determine it the shape modeequals a circle. If it is, block 426 is utilized to determine a set ofcoordinates for a polygon which approximates a circle, i.e. a set ofpoints equidistant from the cursor in the plane of the view. Some numberN of points is selected which, given the resolution of the particularmachines used, will look like a circle to the user.

If at block 418 it was determined that the shape mode was not a circle,decision block 420 is utilized to determine if the mode is user definedpolygon. If so, block 432 is utilized to convert a user definition ofpoints relative to the cursor position to absolute points for the lockrecord.

The graphics editing environment also allows for a cursor lock modeequal to a current object over which the cursor is located. If at block420 it was determined that the mode was not polygon mode, block 422 isutilized to determine if object mode is in use. If yes, block 430 isutilized to query the display image to determine if the cursor is overan object. If yes, block 432 is utilized to query the object for itsabsolute bounding points, which are used as defining points for apolygon shaped cursor lock record.

From blocks 424, 426, 428 and 432, i.e. from any definition of thebounds for a cursor lock, decision block 434 is utilized to compare thenew lock record to other lock records for a possible conflict (See FIG.29B for details). If no conflict is found the old lock record is removed(block 444) and the pointer field in the cursor record is reset theupdating to the new lock record (block 446). Block 447 then illustratesthe updating of the display. The process returns to the appropriatepoint in the editing process. If however, a conflict is found atdecision block 434, or no object is found below the cursor (block 430),or the lock mode was found to not be in Object mode (block 422, implyingthat automatic association of a lock to a cursor is off), then block 436is utilized to delete the newly created lock record. Next, block 438 isutilized to determine if the current cursor position is within its ownold lock record. If it is, the old lock record is allowed to stand,although visually the cursor is no longer centered in its lock region.If the cursor is outside of its old cursor lock, the old cursor lock iseliminated by deletion of the lock record indicated by the cursor lockpointer in the cursor record (block 440) and resetting that pointer tonull. Block 447 then illustrates the updating of the display.

Establishment of a user select region is a preliminary step toestablishment by a user of an associational type or user select locktype region. Referring to FIG. 25A, a flow chart illustratesestablishing a select region in a textual document. The perform selectprocess is begun by selection of a select point in the editing process.Decision block 448 is utilized to determine if a second point of theselect has been entered, which is required to continue the process. If asecond select point is not received, the process is returned to theappropriate point in the editing process. A user may select as a secondpoint the same point as was identified as the first select point,permitting creation of a select region of a single character.

From block 450, indicating receipt of a second select point, block 452is utilized to create an association/lock record having as its start andend, the first and second select points in an appropriate order. Therecord type is set to "SELECT LOCK". Next, block 454 is utilized todetermine if the new select region conflicts with any lock regions(again utilizing the process of FIG. 29A). If it does conflict, block456 is utilized to warn the user that the select has failed and todelete the record. The process is then returned to the appropriate pointin the editor. If no conflict was found at block 454, block 458 isutilized to set the selection field in the cursor record to "ON", block460 is utilized to add the record to the select lock field and thedisplay is updated (block 462) before return of the process to theappropriate point in the editor.

Referring to FIG. 25B, a flow chart illustrates establishing a selectregion in a graphics document. The perform select process is begun byselection of a select point during editing. The process is picked up inthe flow chart with utilization of block 464 to create aassociation/lock record of the select type. It has a shape indicated tobe a polygon and its first point is the initial select point. Next,decision block 466 is utilized to determine if the user has selected asquare (or rectangular) shape for select region. If yes, block 468 isutilized to prompt the user to supply a second point to define theregion. A user may select as a second point the same point as wasidentified as the first select point, permitting creation of a selectregion of a single pixel.

If a square shape is not selected, block 470 is utilized to determine ifthe user has selected a circular shape. If yes, block 472 is utilized toprompt the user to supply a radius, from which the next N select pointscan be generated to complete a substantially circular appearing polygon.

If a circular shape was not determined at block 470, decision block 474is utilized to determine is a general polygon was selected by the user.If yes, the user is prompted to supply a series of points through block476. The user may, instead of selection of an additional point signalthe machine that all points have been supplied, which is detectedutilizing decision block 478. After determining that the user is done,the polygon is closed and the process passes out of the loop along theYES branch from decision block 478. As long as the user does not signalcompletion, or until the user has selected the maximum number ofpermissible points, the process proceeds along the NO branch from block478 to block 480, which adds the most recent selection to the list ofpoints in the association/lock record, and then returns to block 476.

The NO branch from decision block 474 indicates that a user has failedto select a shape for the user select region, resulting in return of theprocess to the appropriate point in the editing process, afterindicating error to the user and deletion of the record created at block464 (block 482).

Upon completion of the boundary points of the user select region,decision block 484 is utilized to determine if the new record conflictswith another lock record (see FIG. 29B). If yes, block 492 is utilizedto warn the user. Next, block 494 is utilized to delete the recordcreated at block 464. The process is thereupon returned to theappropriate point in the editor.

If no conflict is detected at decision block 484, the process passesalong the NO branch to operation block 486, which is utilized to the setselection field in the cursor record to "ON". Next, block 488 isutilized to fill in a pointer field in the association record list ofthe cursor record. Then, if operation is in the client, block 490 isutilized to update the display to indicate select of a region. Theprocess is then returned to the appropriate point in the editor.

A set lock operation to convert a select region to a user select lockregion is the same for both embodiments. Referring to FIG. 26, a flowchart relating user establishment of a lock region from a select regionis depicted. Upon a request to set a lock, the process utilizes block496 to determine if the select on field in the cursor record for theuser is ON. If not the request is invalid and the process is returned tothe appropriate point in the editor without substantial action. If theselect on field is on, and if in the client, block 498 is utilized toupdate the display to remove the select indication from the regionpointed to in the cursor record. Block 500 is utilized to remove therecord from the select lock field and place it in the user lock list, ifsuch a distinction is maintained in cursor records. Next, block 502 isutilized to reset the type field in the lock record to "user lock".Then, block 504 is utilized to reset the select on fields in the cursorrecord and the lock record to OFF. Lastly, before return to the editor,block 506 is executed to update the display to reflect the new lockregion.

FIG. 27 depicts a flow chart relating to user designation of a selectregion as an associated region. Upon a request to perform an associationoperation, the process utilizes block 508 to determine if the select onfield in the cursor record for the user is ON. If not, the request isinvalid and the process is returned to the appropriate point in theeditor without substantial action. If the select on field is on, and ifthe process is in the client, block 510 is utilized to update thedisplay to remove the select indication from the region pointed to inthe cursor record. Block 512 is utilized to remove the region from theselect lock field and put it in the association list, if such adistinction is maintained in cursor records. Next, block 514 is utilizedto reset the type field in the lock record to "user association". Then,block 516 is utilized to reset the select on fields in the cursor recordand the association/lock record to OFF. Lastly, before return to theeditor, block 518 is executed to update the display to reflect the newassociation region.

User release of lock and association regions is next illustrated.Referring to FIG. 28, a flow chart relating to unlocking ordisassociation of regions is illustrated. The process is initiated atblock 520 with the setting of a flag to indicate if an unlock or adisassociation operation is being undertaken. The process will examineeach record in the cursor lock and association lists until one islocated in which the cursor is located. This process utilizes decisionblock 522, which determines if records exist in the user select locklist or association list for possible elimination. If such records existthey are recovered in the order of the list (block 524) and decisionblock 526 is utilized to determine if the cursor is within the bounds ofthe record. If not, the process returns to block 522. If a record isfound in which the cursor lies, block 527 illustrates a determination ofwhether or not the current user is the owner of the record. If not, theprocess returns to block 522. If so, the pointer to the record isremoved from the appropriate list in the cursor record. Next, at block530, the record itself is released. Lastly, block 532 is utilized toupdate the display (again only in client terminals). The process is thenreturned to the appropriate point in the editor.

FIGS. 29A and 29B are flow charts relating to first and secondembodiments of the invention providing for detection of lock conflicts,which are made upon user attempts to select a region or upon an attemptto move a cursor lock. Referring to FIG. 29A, there is illustrated sucha comparison for a text editing environment. The process begins with aninquiry relating to the presence of user select lock or cursor lockrecords. If none exist or remain, the inquiry is complete and the NObranch from block 534 is taken back to the requesting routine,indicating to the requesting routine that no conflict exists. If recordsremain, the next such record is retrieved utilizing block 536. Decisionblock 538 is utilized to determine if the current cursor is the owner ofthe record. If yes, the record can be disregarded and the processreturns to block 534 on the YES branch from block 538. Along the NObranch, decision block 540 is utilized to determine if a the record is alock of either type. If not, the record may be disregarded and theprocess returns to block 534. If yes, determination is made if therequested select or lock region has common points with the lock record.Decision block 542 is utilized to determine if the lock (select) regioninput start occurs with or after the recovered lock record start. Ifyes, block 546 is utilized to determine if the input record start occursbefore or with the end of the recovered lock record end. If it does, aconflict is present and such indication is returned to the requestingprocess. If it does not so occur, the process returns to block 534 andexamination of the next record. Along the NO branch from decision block542, the process utilizes decision block 544 to determine if the inputrecord end occurs after or with the lock record start. If not, noconflict exists and the process returns to block 534. If yes, a conflictexists and operation is returned to the requesting process with anindication of the conflict.

Referring to FIG. 29B, there is illustrated such a comparison for agraphics editing environment. The process begins with an inquiryrelating to the presence of user select lock or cursor lock records. Ifno records exist or remain, the inquiry is complete and the NO branchfrom block 548 is taken back to the requesting routine, indicating tothe requesting routine that no conflict exists. If records remain, thenext such record is retrieved utilizing block 550. Next, decision block552 is utilized to determine if the current cursor is the owner of therecord. If yes, the record can be disregarded and the process returns toblock 548 on the YES branch from block 552. Along the NO branch,decision block 554 is utilized to determine if a the record is a lock ofeither type. If not, the record may be disregarded and the processreturns to block 548. If yes, the record and the input region must becompared for possible overlap. Decision block 556 is used to determinesuch overlap. The test is one to determine if the polygon of the inputregion overlap the polygon that is returned from the lock recordrecovered at block 550. If they do, a conflict indication is returned tothe requesting process. If no overlap is found, the process returns toblock 548 for examination of further records.

With reference now to FIG. 30, a flowchart for processing local eventsin accordance with a preferred embodiment of the present invention isdepicted. The process begins in block 700 and thereafter proceeds toblock 702. Block 702 is utilized to illustrate a determination ofwhether or not the event is a local create notification region event.The occurrence of a local create notification region event results inthe process passing to block 704, which illustrates the prompting of theuser to define notification region boundary. Notification regionboundary may be defined in various ways in accordance with a preferredembodiment of the present invention. A user may employ a mouse to definethe various boundaries for the notification region, defining various x,ypositions within a window. Alternatively, the user may utilize a cursoror some other series of keys to define the region. In a text onlysituation, lines and offset values may be utilized to define a region,in accordance with a preferred embodiment of the present invention.

Next, block 706 illustrates prompting the user to specify a notificationmessage. Thereafter, the process proceeds to block 708. Block 708depicts prompting the user to define a list of users who may trigger thenotification. This list of users may be selected users or may includeall users having access to the shared data object. Next, as illustratedin block 710, the user is prompted to define a list of users who willreceive the notification when the notification region is triggered. Theuser may designate selected users or all users to receive thenotification message. For example, the user triggering the notificationmessage may be selected to receive the message, in accordance with apreferred embodiment of the present invention. Various differentselections of users may be selected by the user to receive anotification message. The process then proceeds to block 712. Block 712illustrates the placement of the information entered by the user into a"create notification region" (CNR) message. Block 714 illustrates thetransmission of the message to the central server for distribution toother nodes. The process thereafter terminates, as depicted in block716.

Referring again to block 702, if the event is not a local create andnotification region event, the process then passes to block 718.Decision block 718 illustrates a determination of whether or not theevent is a local cancel notification region event. Upon the occurrenceof a local cancel notification region event, the process then proceedsto block 720. Block 720 illustrates a determination of whether or notmore regions exist in the notification region list. If the answer is NO,the process terminates at block 710. If the answer is YES, block 722 isutilized to illustrate a retrieval of the next region from thenotification region list. The process then passes to block 724. Block724 illustrates a determination of whether or not the user's cursor iswithin retrieved region. If the user's cursor is not within the region,the process returns to block 720 in an iterative fashion.

If the user's cursor is within the region, the process then proceeds toblock 726. Block 726 is utilized to illustrate prompting the user thatthe region is about to be cancelled. Thereafter, block 728 is utilizedto determination of whether or not the user desires to continue if theuser does not desire to continue, the process returns to block 720. Ifthe user indicates that he or she wishes to continue, the process thenproceeds to block 730. Block 730 illustrates the creation of a "cancelnotification region" message and the message is transmitted to thecentral server for distribution to other nodes, as illustrated in block731. Thereafter, the process returns to block 720.

Referring again to block 718, if the event is not a local cancelnotification region event, the process then proceeds to block 732, whichillustrates a determination of whether or not the event is a localbroadcast event. Upon the occurrence of a local broadcast event, theprocess then passes to block 734. Block 734 illustrates prompting theuser to define a bounding region containing cursors of users to whom amessage may be broadcast. Thereafter, the process proceeds to block 736,which depicts prompting the user to define the message for broadcast toother users.

Next, the process proceeds to block 738. Block 738 illustrates adetermination of whether or not more cursors are in the "cursor list".If the answer is NO, the process terminates as illustrated in block 710.The existence of more cursors within the cursor list results in theprocess proceeding to block 739, which illustrates the retrieval of thenext cursor from the cursor list. Thereafter, the process proceeds toblock 741. Block 741 depicts a determination of whether or not thecursor retrieved from the cursor list is within the region defined forbroadcast messages. If the cursor is within the region, the process thenproceeds to block 740. Block 740 illustrates the creation of a broadcastcommand message that is addressed to the cursor's owner. Thereafter, theprocess proceeds to block 742. Block 742 illustrates the transmission ofbroadcast command message to the central server for distribution toother nodes. The process then returns to block 738. Referring back toblock 741, if the cursor retrieved is not within the bounding region,the process returns to block 738.

Referring again to block 732, if the event is not a local broadcastevent, the process then passes to block 744. Block 744 depicts adetermination of whether or not the event is some other global editingcommand. If the event is some other global editing command, the processproceeds to block 746, which depicts the creation of the appropriatecommand message, and the transmission of the message to the centralserver for distribution to other nodes, as illustrated in block 747.Thereafter the process terminates, as illustrated in block 710.Referring again to block 744, if the event is not some other globalediting command, the process then passes to block 745. Block 745illustrates the processing of a command locally.

An alternate embodiment has been contemplated that transmits designatedmessages to users aurally instead of or in addition to textually. Inthis embodiment, the designated messages are stored as speech fortransmission in response to selected activities of one or more userswithin the designated region. Speech can be recorded and stored forplayback through use of a sound card plugged into computer 12 (FIG. 1),such as a Creative Labs Sound Blaster Pro card. Textual messages canalso be converted into speech through a variety of text to speechconverters known in the art.

Although the invention has been described with reference to a specificembodiment, this description is not meant to be construed in a limitingsense. Various modifications of the disclosed embodiment as well asalternative embodiments of the invention will become apparent to personsskilled in the art upon reference to the description of the invention.It is therefore contemplated that the appended claims will cover anysuch modifications or embodiments that fall within the true scope of theinvention.

We claim:
 1. A method of communications management within acollaborative computer-based system a plurality of display devices, ashared data object simultaneously accessible by a plurality of users,means for displaying portions of said shared data object within each ofsaid plurality of display devices, and means for providing a pluralityof cursors within said shared data object, wherein each of saidplurality of cursors is associated with one of said plurality of users,said method comprising computer implemented steps of:entering a mode inwhich messages are sent in response to selected events by said pluralityof users; determining whether a cursor movement event has occurred; inresponse to a cursor movement event occurring, determining whether acursor movement event has resulted in a cursor moving within adesignated notification region within said shared data object; inresponse to a cursor moving into the designated notification region,identifying users to receive said message; and displaying said messageto said identified users.
 2. The method for claim 1, wherein the step ofdisplaying comprises:determining whether a received once mode has beenset for a user; determining whether said user has received the messagebefore in response to a determination that a receive once mode has beenset for the user; and displaying said message to said user in responseto an absence of an indication that said user has received said messagebefore.
 3. A method of communications management within a collaborativecomputer-based system a plurality of display devices, a shared dataobject simultaneously accessible by a plurality of users, means fordisplaying portions of said shared data object within each of saidplurality of display devices, and means for providing a plurality ofcursors within said shared data object, wherein each of said pluralityof cursors is associated with one of said plurality of users, saidmethod comprising computer implemented steps of:entering a mode in whichmessages are sent in response to selected events by said plurality ofusers; defining a notification region within said shared data object,said defined notification region containing cursors; defining a messageto send; and sending said message to each user having a cursor withinsaid defined notification region.
 4. A communications management systemwithin a collaborative computer-based system a plurality of displaydevices, a shared data object simultaneously accessible by a pluralityof users, means for displaying portions of said shared data objectwithin each of said plurality of display devices, and means forproviding a plurality of cursors within said shared data object, whereineach of said plurality of cursors is associated with one of saidplurality of users, said communications management systemcomprising:means for entering a mode in which messages are sent responseto selected events by said plurality of users; determination means fordetermining whether a cursor movement event has occurred; firstresponsive means for responding to a cursor movement event occurring,determining whether a cursor movement event has resulted in a cursormoving within a designated notification region within said shared dataobject; second responsive means for responding to a cursor moving intothe designated notification region, identifying users to receive amessage; and display means for displaying said message to saididentified users.
 5. The communications management system of claim 4,wherein the step of displaying comprises:determination means fordetermining whether a received once mode has been set for a user;determination means for determining whether said user has received themessage before in response to a determination that a receive once modehas been set for the user; and display means for displaying said messageto said user in response to an absence of an indication that said userhas received said message before.
 6. A communications management systemwithin a collaborative computer-based system a plurality of displaydevices, a shared data object simultaneously accessible by a pluralityof users, means for displaying portions of said shared data objectwithin each of said plurality of display devices, and means forproviding a plurality of cursors within said shared data object, whereineach of said plurality of cursors is associated with one of saidplurality of users, said communications management systemcomprising:means for entering a mode in which messages are sent inresponse to selected events by said plurality of users; definition meansfor defining a notification region within said shared data object, saiddefined notification region containing cursors; definition means fordefining a message to send; and sending means for sending said messageto each user having a cursor within said defined notification region.